Question

As observed on earth, a certain type of bacteria is known to double
in number every 27.3 hours. Two cultures of these bacteria are
prepared, each consisting initially of one bacterium. One culture
is left on earth and the other placed on a rocket that travels at a
speed of 0.787c relative to the earth. At a time when the
earthbound culture has grown to 32 bacteria, how many bacteria are
in the culture on the rocket, according to an earth-based
observer?